Micro Sandpaper Detailing Tool

I was sure someone had already done this or something similar, but google searches didn't reveal any and searching on Amazon only produced things such as this:

https://www.amazon.com/Lumberton-12301-Sanding-Sti...

Which at $30 and only very rough grit would not serve my need.

I wanted:

• Flexible tip to get into very small spaces (<1/8")
• Variety of grit size
• Wet sandpaper
• Most importantly, inexpensive

My use is primarily to do finish detailing on 3D printed SLA (liquid resin) parts like the picture above, but these can be used for any purpose.

I was surprised how well they stood up to very aggressive use. In working on the part shown, I was applying as much force as I could and did not have a single one where the sandpaper circle separated from the Q-Tip tip. Each one basically lasted until the sandpaper itself was no longer useful.

(All pictures in this Instructable are of 1600 grit wet sandpaper.)

Supplies

1. Sandpaper
   • Dry or wet - though I only tried this with wet
   • Grit doesn't matter, though rougher grit will take a toll on your hole punch
2. Hole punch
   • 3 ring binder punch works best as it catches the circles in the base
3. Q-Tips
   • Any brand, but I used the name brand
4. Hot glue gun
   • Just the standard glue sticks, nothing special
5. Plastic razor blades
   • Metal ones are fine too or a sharp flat non-serrated knife

Step 1: Creating the "Holders" and "Discs"

I chose to cut the Q-Tips in half, but they can be left whole if you choose.

Cut the discs you need from the sandpaper sheet. This 1600 grit paper didn't catch or clog up the hole punch at all.

Step 2: Preparing the Q-Tip Tips (Step #1)

This step, I found, is crucial. (I first tried simply gluing the discs directly to the Q-Tip tip but it did not hold up well at all.)

1. The goal is simply to saturate the cotton with the hot glue. Hold the gun in place, while spinning the Q-Tip.
2. Try not to add too much, the bigger the saturated tip is it will prevent the final tool from going into small corners
3. Immediately after saturating the cotton while the hot glue is still "liquidy" press onto a flat surface to create a flat spot at the tip that can also be separated from the surface later. I did these on a wooden work bench.
4. Allow to cool and completely re-solidify

You can place them perfectly vertical like I did in the second image above, or place them at an angle (you'll need something to support them from falling completely over). If done at an angle, you can create ones that can be held more like a pencil. (For ones done this way, I'd probably leave the Q-Tips whole so it can rest in your hand like a pen/pencil.)

Step 3: Preparing the Q-Tip Tips (Step #2)

Use a sharp blade (I use these plastic razor blades - link below) to gently separate the Q-Tip tips after cooling.

If any have a flat end where the surface area is bigger than the discs, you'll want to trim that excess away.

https://www.amazon.com/gp/product/B073X843MN/ref=p...

Step 4: Applying the Discs

1. Flip the sandpaper discs over so that the rough side is facing down.
2. Apply a small drop of hot glue to the Q-Tip tip (not to the disc - it will just stick to the gun's tip)
3. Stick each Q-Tip tip onto a disc
4. Flip over and stick the cut end of the Q-tip into a foam block or other way to hold it vertically until the hot glue cools

ALL DONE!

Thank You for taking your time to read though my Instructable. Let me know if it was a helpful idea or if you have any questions/suggestions.